Commit Graph

1245 Commits

Author SHA1 Message Date
Jiri Slaby
2423fdfb96 Btrfs, fix memory leaks in error paths
Stanse found 2 memory leaks in relocate_block_group and
__btrfs_map_block. cluster and multi are not freed/assigned on all
paths. Fix that.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: linux-btrfs@vger.kernel.org
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-01-17 20:40:20 -05:00
Yan, Zheng
a038fab0cb Btrfs: align offsets for btrfs_ordered_update_i_size
Some callers of btrfs_ordered_update_i_size can now pass in
a NULL for the ordered extent to update against.  This makes
sure we properly align the offset they pass in when deciding
how much to bump the on disk i_size.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-01-17 20:06:27 -05:00
Jan Engelhardt
406266ab9a btrfs: fix missing last-entry in readdir(3)
parent 49313cdac7b34c9f7ecbb1780cfc648b1c082cd7 (v2.6.32-1-g49313cd)
commit ff48c08e1c05c67e8348ab6f8a24de8034e0e34d
Author: Jan Engelhardt <jengelh@medozas.de>
Date:   Wed Dec 9 22:57:36 2009 +0100

Btrfs: fix missing last-entry in readdir(3)

When one does a 32-bit readdir(3), the last entry of a directory is
missing. This is however not due to passing a large value to filldir,
but it seems to have to do with glibc doing telldir or something
quirky. In any case, this patch fixes it in practice.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-01-17 20:06:27 -05:00
Chris Mason
3a1abec9f6 Btrfs: make sure fallocate properly starts a transaction
The recent patch to make fallocate enospc friendly would send
down a NULL trans handle to the allocator.  This moves the
transaction start to properly fix things.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 15:47:17 -05:00
Josef Bacik
83d3c9696f Btrfs: make metadata chunks smaller
This patch makes us a bit less zealous about making sure we have enough free
metadata space by pearing down the size of new metadata chunks to 256mb instead
of 1gb.  Also, we used to try an allocate metadata chunks when allocating data,
but that sort of thing is done elsewhere now so we can just remove it.  With my
-ENOSPC test I used to have 3gb reserved for metadata out of 75gb, now I have
1.7gb.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:38 -05:00
Matthew Wilcox
20a5239a5d Btrfs: Show discard option in /proc/mounts
Christoph's patch e244a0aeb6 doesn't display
the discard option in /proc/mounts, leading to some confusion for me.
Here's the missing bit.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:37 -05:00
TARUISI Hiroaki
4a8be425a8 Btrfs: deny sys_link across subvolumes.
I rebased Christian Parpart's patch to deny hard link across
subvolumes. Original patch modifies also btrfs_rename, but
I excluded it because we can move across subvolumes now and
it make no problem.
-----------------

Hard link across subvolumes should not allowed in Btrfs.
btrfs_link checks root of 'to' directory is same as root
of 'from' file. If not same, btrfs_link returns -EPERM.

Signed-off-by: TARUISI Hiroaki <taruishi.hiroak@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:37 -05:00
Sage Weil
a7a3f7cadd Btrfs: fail mount on bad mount options
We shouldn't silently ignore unrecognized options.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:36 -05:00
Yan, Zheng
06b2331f83 Btrfs: don't add extent 0 to the free space cache v2
If block group 0 is completely free, btrfs_read_block_groups will
add extent [0, BTRFS_SUPER_INFO_OFFSET) to the free space cache.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:36 -05:00
Yan, Zheng
86b9f2eca5 Btrfs: Fix per root used space accounting
The bytes_used field in root item was originally planned to
trace the amount of used data and tree blocks. But it never
worked right since we can't trace freeing of data accurately.
This patch changes it to only trace the amount of tree blocks.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:35 -05:00
Yan, Zheng
55ef689900 Btrfs: Fix btrfs_drop_extent_cache for skip pinned case
The check for skip pinned case is wrong, it may breaks the
while loop too soon.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:35 -05:00
Yan, Zheng
24bbcf0442 Btrfs: Add delayed iput
iput() can trigger new transactions if we are dropping the
final reference, so calling it in btrfs_commit_transaction
may end up deadlock. This patch adds delayed iput to avoid
the issue.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:35 -05:00
Yan, Zheng
f34f57a3ab Btrfs: Pass transaction handle to security and ACL initialization functions
Pass transaction handle down to security and ACL initialization
functions, so we can avoid starting nested transactions

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:34 -05:00
Yan, Zheng
8082510e71 Btrfs: Make truncate(2) more ENOSPC friendly
truncating and deleting regular files are unbound operations,
so it's not good to do them in a single transaction. This
patch makes btrfs_truncate and btrfs_delete_inode start a
new transaction after all items in a tree leaf are deleted.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:34 -05:00
Yan, Zheng
5a303d5d4b Btrfs: Make fallocate(2) more ENOSPC friendly
fallocate(2) may allocate large number of file extents, so it's not
good to do it in a single transaction. This patch make fallocate(2)
start a new transaction for each file extents it allocates.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:33 -05:00
Yan, Zheng
2e4bfab970 Btrfs: Avoid orphan inodes cleanup during committing transaction
btrfs_lookup_dentry may trigger orphan cleanup, so it's not good
to call it while committing a transaction.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:33 -05:00
Yan, Zheng
c71bf099ab Btrfs: Avoid orphan inodes cleanup while replaying log
We do log replay in a single transaction, so it's not good to do unbound
operations. This patch cleans up orphan inodes cleanup after replaying
the log. It also avoids doing other unbound operations such as truncating
a file during replaying log. These unbound operations are postponed to
the orphan inode cleanup stage.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:33 -05:00
Yan, Zheng
c216775458 Btrfs: Fix disk_i_size update corner case
There are some cases file extents are inserted without involving
ordered struct. In these cases, we update disk_i_size directly,
without checking pending ordered extent and DELALLOC bit. This
patch extends btrfs_ordered_update_i_size() to handle these cases.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-17 12:33:24 -05:00
Yan, Zheng
920bbbfb05 Btrfs: Rewrite btrfs_drop_extents
Rewrite btrfs_drop_extents by using btrfs_duplicate_item, so we can
avoid calling lock_extent within transaction.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-15 21:24:52 -05:00
Yan, Zheng
ad48fd7546 Btrfs: Add btrfs_duplicate_item
btrfs_duplicate_item duplicates item with new key, guaranteeing
the source item and the new items are in the same tree leaf and
contiguous. It allows us to split file extent in place, without
using lock_extent to prevent bookend extent race.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-15 21:24:25 -05:00
Yan, Zheng
8cef4e160d Btrfs: Avoid superfluous tree-log writeout
We allow two log transactions at a time, but use same flag
to mark dirty tree-log btree blocks. So we may flush dirty
blocks belonging to newer log transaction when committing a
log transaction. This patch fixes the issue by using two
flags to mark dirty tree-log btree blocks.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-12-15 21:24:25 -05:00
Linus Torvalds
aa021baa32 Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: fix panic when trying to destroy a newly allocated
  Btrfs: allow more metadata chunk preallocation
  Btrfs: fallback on uncompressed io if compressed io fails
  Btrfs: find ideal block group for caching
  Btrfs: avoid null deref in unpin_extent_cache()
  Btrfs: skip btrfs_release_path in btrfs_update_root and btrfs_del_root
  Btrfs: fix some metadata enospc issues
  Btrfs: fix how we set max_size for free space clusters
  Btrfs: cleanup transaction starting and fix journal_info usage
  Btrfs: fix data allocation hint start
2009-11-11 13:38:59 -08:00
Josef Bacik
a6dbd429d8 Btrfs: fix panic when trying to destroy a newly allocated
There is a problem where iget5_locked will look for an inode, not find it, and
then subsequently try to allocate it.  Another CPU will have raced in and
allocated the inode instead, so when iget5_locked gets the inode spin lock again
and does a search, it finds the new inode.  So it goes ahead and calls
destroy_inode on the inode it just allocated.  The problem is we don't set
BTRFS_I(inode)->root until the new inode is completely initialized.  This patch
makes us set root to NULL when alloc'ing a new inode, so when we get to
btrfs_destroy_inode and we see that root is NULL we can just free up the memory
and continue on.  This fixes the panic

http://www.kerneloops.org/submitresult.php?number=812690

Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 15:53:34 -05:00
Chris Mason
33b2580864 Btrfs: allow more metadata chunk preallocation
On an FS where all of the space has not been allocated into chunks yet,
the enospc can return enospc just because the existing metadata chunks
are full.

We get around this by allowing more metadata chunks to be allocated up
to a certain limit, and finding the right limit is a little fuzzy.  The
problem is the reservations for delalloc would preallocate way too much
of the FS as metadata.  We need to start saying no and just force some
IO to happen.

But we also need to let a reasonable amount of the FS become metadata.
This bumps the hard limit up, later releases will have a better system.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 14:20:20 -05:00
Josef Bacik
f5a84ee3cd Btrfs: fallback on uncompressed io if compressed io fails
Currently compressed IO does not deal with not having its entire extent able to
be allocated.  So if we have enough free space to allocate for the extent, but
its not contiguous, it will fail spectacularly.  This patch fixes this by
falling back on uncompressed IO which lets us spread the delalloc extent across
multiple extents.  I tested this by making us randomly think the reservation had
failed to make it fallback on the uncompressed io way and it seemed to work
fine.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 14:20:20 -05:00
Josef Bacik
ccf0e72537 Btrfs: find ideal block group for caching
This patch changes a few things.  Hopefully the comments are helpfull, but
I'll try and be as verbose here.

Problem:

My fedora box was taking 1 minute and 21 seconds to boot with btrfs as root.
Part of this problem was we pick the first block group we can find and start
caching it, even if it may not have enough free space.  The other problem is
we only search for cached block groups the first time around, which we won't
find any cached block groups because this is a newly mounted fs, so we end up
caching several block groups during bootup, which with alot of fragmentation
takes around 30-45 seconds to complete, which bogs down the system.  So

Solution:

1) Don't cache block groups willy-nilly at first.  Instead try and figure out
which block group has the most free, and therefore will take the least amount
of time to cache.

2) Don't be so picky about cached block groups.  The other problem is once
we've filled up a cluster, if the block group isn't finished caching the next
time we try and do the allocation we'll completely ignore the cluster and
start searching from the beginning of the space, which makes us cache more
block groups, which slows us down even more.  So instead of skipping block
groups that are not finished caching when we have a hint, only skip the block
group if it hasn't started caching yet.

There is one other tweak in here.  Before if we allocated a chunk and still
couldn't find new space, we'd end up switching the space info to force another
chunk allocation.  This could make us end up with way too many chunks, so keep
track of this particular case.

With this patch and my previous cluster fixes my fedora box now boots in 43
seconds, and according to the bootchart is not held up by our block group
caching at all.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 14:20:19 -05:00
Dan Carpenter
4eb3991c5d Btrfs: avoid null deref in unpin_extent_cache()
I re-orderred the checks to avoid dereferencing "em" if it was null.

Found by smatch static checker.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 14:20:18 -05:00
Li Dongyang
df66916e71 Btrfs: skip btrfs_release_path in btrfs_update_root and btrfs_del_root
We don't need to call btrfs_release_path because btrfs_free_path will do
that for us.

Signed-off-by: Li Dongyang <Jerry87905@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 14:20:18 -05:00
Josef Bacik
5df6a9f606 Btrfs: fix some metadata enospc issues
We weren't reserving metadata space for rename, rmdir and unlink, which could
cause problems.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 14:20:17 -05:00
Josef Bacik
01dea1efc2 Btrfs: fix how we set max_size for free space clusters
This patch fixes a problem where max_size can be set to 0 even though we
filled the cluster properly.  We set max_size to 0 if we restart the cluster
window, but if the new start entry is big enough to be our new cluster then we
could return with a max_size set to 0, which will mean the next time we try to
allocate from this cluster it will fail.  So set max_extent to the entry's
size.  Tested this on my box and now we actually allocate from the cluster
after we fill it.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 14:20:17 -05:00
Josef Bacik
249ac1e55c Btrfs: cleanup transaction starting and fix journal_info usage
We use journal_info to tell if we're in a nested transaction to make sure we
don't commit the transaction within a nested transaction.  We use another
method to see if there are any outstanding ioctl trans handles, so if we're
starting one do not set current->journal_info, since it will screw with other
filesystems.  This patch also cleans up the starting stuff so there aren't any
magic numbers.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 14:20:16 -05:00
Josef Bacik
6346c93988 Btrfs: fix data allocation hint start
Sometimes our start allocation hint when we cow a file can be either
EXTENT_HOLE or some other such place holder, which is not optimal.  So if we
find that our em->block_start is one of these special values, check to see
where the first block of the inode is stored, and use that as a hint.  If that
block is also a special value, just fallback on a hint of 0 and let the
allocator figure out a good place to put the data.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-11-11 14:20:16 -05:00
Linus Torvalds
dcbeb0bec5 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: always pin metadata in discard mode
  Btrfs: enable discard support
  Btrfs: add -o discard option
  Btrfs: properly wait log writers during log sync
  Btrfs: fix possible ENOSPC problems with truncate
  Btrfs: fix btrfs acl #ifdef checks
  Btrfs: streamline tree-log btree block writeout
  Btrfs: avoid tree log commit when there are no changes
  Btrfs: only write one super copy during fsync
2009-10-15 15:06:37 -07:00
Chris Mason
444528b3e6 Btrfs: always pin metadata in discard mode
We have an optimization in btrfs to allow blocks to be
immediately freed if they were allocated in this transaction and never
written.  Otherwise they are pinned and freed when the transaction
commits.

This isn't optimal for discard mode because immediately freeing
them means immediately discarding them.  It is better to give the
block to the pinning code and letting the (slow) discard happen later.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-14 10:32:50 -04:00
Christoph Hellwig
0634857488 Btrfs: enable discard support
The discard support code in btrfs currently is guarded by ifdefs for
BIO_RW_DISCARD, which is never defines as it's the name of an enum
memeber.  Just remove the useless ifdefs to actually enable the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-14 10:32:49 -04:00
Christoph Hellwig
e244a0aeb6 Btrfs: add -o discard option
Enable discard by default is not a good idea given the the trim speed
of SSD prototypes we've seen, and the carecteristics for many high-end
arrays.  Turn of discards by default and require the -o discard option
to enable them on.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-14 10:32:49 -04:00
Yan, Zheng
86df7eb921 Btrfs: properly wait log writers during log sync
A recently fsync optimization make btrfs_sync_log skip calling
wait_for_writer in the single log writer case. This is incorrect
since the writer count can also be increased by btrfs_pin_log.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-14 10:32:48 -04:00
Josef Bacik
5d5e103a70 Btrfs: fix possible ENOSPC problems with truncate
There's a problem where we don't do any space reservation for truncates, which
can cause you to OOPs because you will be allowed to go off in the weeds a bit
since we don't account for the delalloc bytes that are created as a result of
the truncate.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-14 10:32:47 -04:00
Chris Mason
0eda294dfc Btrfs: fix btrfs acl #ifdef checks
The btrfs acl code was #ifdefing for a define
that didn't exist.  This correctly matches it
to the values used by the Kconfig file.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-13 13:51:39 -04:00
Chris Mason
690587d109 Btrfs: streamline tree-log btree block writeout
Syncing the tree log is a 3 phase operation.

1) write and wait for all the tree log blocks for a given root.

2) write and wait for all the tree log blocks for the
tree of tree log roots.

3) write and wait for the super blocks (barriers here)

This isn't as efficient as it could be because there is
no requirement to wait for the blocks from step one to hit the disk
before we start writing the blocks from step two.  This commit
changes the sequence so that we don't start waiting until
all the tree blocks from both steps one and two have been sent
to disk.

We do this by breaking up btrfs_write_wait_marked_extents into
two functions, which is trivial because it was already broken
up into two parts.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-13 13:35:12 -04:00
Chris Mason
257c62e1bc Btrfs: avoid tree log commit when there are no changes
rpm has a habit of running fdatasync when the file hasn't
changed.  We already detect if a file hasn't been changed
in the current transaction but it might have been sent to
the tree-log in this transaction and not changed since
the last call to fsync.

In this case, we want to avoid a tree log sync, which includes
a number of synchronous writes and barriers.  This commit
extends the existing tracking of the last transaction to change
a file to also track the last sub-transaction.

The end result is that rpm -ivh and -Uvh are roughly twice as fast,
and on par with ext3.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-13 13:35:12 -04:00
Chris Mason
4722607db6 Btrfs: only write one super copy during fsync
During a tree-log commit for fsync, we've been writing at least
two copies of the super block and forcing them to disk.

The other filesystems write only one, and this change brings us on
par with them.  A full transaction commit will write all the super
copies, so we still have redundant info written on a regular
basis.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-13 13:35:11 -04:00
Linus Torvalds
474a503d4b Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: fix file clone ioctl for bookend extents
  Btrfs: fix uninit compiler warning in cow_file_range_nocow
  Btrfs: constify dentry_operations
  Btrfs: optimize back reference update during btrfs_drop_snapshot
  Btrfs: remove negative dentry when deleting subvolumne
  Btrfs: optimize fsync for the single writer case
  Btrfs: async delalloc flushing under space pressure
  Btrfs: release delalloc reservations on extent item insertion
  Btrfs: delay clearing EXTENT_DELALLOC for compressed extents
  Btrfs: cleanup extent_clear_unlock_delalloc flags
  Btrfs: fix possible softlockup in the allocator
  Btrfs: fix deadlock on async thread startup
2009-10-11 11:23:13 -07:00
Chris Mason
ac6889cbb2 Btrfs: fix file clone ioctl for bookend extents
The file clone ioctl was incorrectly taking the offset into the
extent on disk into account when calculating the length of the
cloned extent.

The length never changes based on the offset into the physical extent.

Test case:

fallocate -l 1g image
mke2fs image
bcp image image2
e2fsck -f image2

(errors on image2)

The math bug ends up wrapping the length of the extent, and things
go wrong from there.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-09 11:29:53 -04:00
Chris Mason
e9061e2148 Btrfs: fix uninit compiler warning in cow_file_range_nocow
The extent_type variable was exposed uninit via a goto.  It should be
impossible to trigger because it is protected by a check on another
variable, but this makes sure.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-09 09:57:45 -04:00
Alexey Dobriyan
82d339d9b3 Btrfs: constify dentry_operations
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-09 09:54:36 -04:00
Yan, Zheng
94fcca9f89 Btrfs: optimize back reference update during btrfs_drop_snapshot
This patch reading level 0 tree blocks that already use full backrefs.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-09 09:25:16 -04:00
Yan, Zheng
efefb1438b Btrfs: remove negative dentry when deleting subvolumne
The use of btrfs_dentry_delete is removing dentries from the
dcache when deleting subvolumne. btrfs_dentry_delete ignores
negative dentries. This is incorrect since if we don't remove
the negative dentry, its parent dentry can't be removed.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-09 09:25:16 -04:00
Josef Bacik
ff782e0a13 Btrfs: optimize fsync for the single writer case
This patch optimizes the tree logging stuff so it doesn't always wait 1 jiffie
for new people to join the logging transaction if there is only ever 1 writer.
This helps a little bit with latency where we have something like RPM where it
will fdatasync every file it writes, and so waiting the 1 jiffie for every
fdatasync really starts to add up.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-08 15:30:04 -04:00
Josef Bacik
e3ccfa9897 Btrfs: async delalloc flushing under space pressure
This patch moves the delalloc flushing that occurs when we are under space
pressure off to a async thread pool.  This helps since we only free up
metadata space when we actually insert the extent item, which means it takes
quite a while for space to be free'ed up if we wait on all ordered extents.
However, if space is freed up due to inline extents being inserted, we can
wake people who are waiting up early, and they can finish their work.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-08 15:21:23 -04:00
Josef Bacik
32c00aff71 Btrfs: release delalloc reservations on extent item insertion
This patch fixes an issue with the delalloc metadata space reservation
code.  The problem is we used to free the reservation as soon as we
allocated the delalloc region.  The problem with this is if we are not
inserting an inline extent, we don't actually insert the extent item until
after the ordered extent is written out.  This patch does 3 things,

1) It moves the reservation clearing stuff into the ordered code, so when
we remove the ordered extent we remove the reservation.
2) It adds a EXTENT_DO_ACCOUNTING flag that gets passed when we clear
delalloc bits in the cases where we want to clear the metadata reservation
when we clear the delalloc extent, in the case that we do an inline extent
or we invalidate the page.
3) It adds another waitqueue to the space info so that when we start a fs
wide delalloc flush, anybody else who also hits that area will simply wait
for the flush to finish and then try to make their allocation.

This has been tested thoroughly to make sure we did not regress on
performance.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-08 15:21:10 -04:00
Chris Mason
a3429ab70b Btrfs: delay clearing EXTENT_DELALLOC for compressed extents
When compression is on, the cow_file_range code is farmed off to
worker threads.  This allows us to do significant CPU work in parallel
on SMP machines.

But it is a delicate balance around when we clear flags and how.  In
the past we cleared the delalloc flag immediately, which was safe
because the pages stayed locked.

But this is causing problems with the newest ENOSPC code, and with the
recent extent state cleanups we can now clear the delalloc bit at the
same time the uncompressed code does.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-08 15:11:50 -04:00
Chris Mason
a791e35e12 Btrfs: cleanup extent_clear_unlock_delalloc flags
extent_clear_unlock_delalloc has a growing set of ugly parameters
that is very difficult to read and maintain.

This switches to a flag field and well named flag defines.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-08 15:11:49 -04:00
Josef Bacik
1cdda9b81a Btrfs: fix possible softlockup in the allocator
Like the cluster allocating stuff, we can lockup the box with the normal
allocation path.  This happens when we

1) Start to cache a block group that is severely fragmented, but has a decent
amount of free space.
2) Start to commit a transaction
3) Have the commit try and empty out some of the delalloc inodes with extents
that are relatively large.

The inodes will not be able to make the allocations because they will ask for
allocations larger than a contiguous area in the free space cache.  So we will
wait for more progress to be made on the block group, but since we're in a
commit the caching kthread won't make any more progress and it already has
enough free space that wait_block_group_cache_progress will just return.  So,
if we wait and fail to make the allocation the next time around, just loop and
go to the next block group.  This keeps us from getting stuck in a softlockup.
Thanks,

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-06 10:04:28 -04:00
Chris Mason
61d92c328c Btrfs: fix deadlock on async thread startup
The btrfs async worker threads are used for a wide variety of things,
including processing bio end_io functions.  This means that when
the endio threads aren't running, the rest of the FS isn't
able to do the final processing required to clear PageWriteback.

The endio threads also try to exit as they become idle and
start more as the work piles up.  The problem is that starting more
threads means kthreadd may need to allocate ram, and that allocation
may wait until the global number of writeback pages on the system is
below a certain limit.

The result of that throttling is that end IO threads wait on
kthreadd, who is waiting on IO to end, which will never happen.

This commit fixes the deadlock by handing off thread startup to a
dedicated thread.  It also fixes a bug where the on-demand thread
creation was creating far too many threads because it didn't take into
account threads being started by other procs.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-05 09:44:45 -04:00
Linus Torvalds
0efe5e32c8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: fix data space leak fix
  Btrfs: remove duplicates of filemap_ helpers
  Btrfs: take i_mutex before generic_write_checks
  Btrfs: fix arguments to btrfs_wait_on_page_writeback_range
  Btrfs: fix deadlock with free space handling and user transactions
  Btrfs: fix error cases for ioctl transactions
  Btrfs: Use CONFIG_BTRFS_POSIX_ACL to enable ACL code
  Btrfs: introduce missing kfree
  Btrfs: Fix setting umask when POSIX ACLs are not enabled
  Btrfs: proper -ENOSPC handling
2009-10-01 20:23:15 -07:00
Alexey Dobriyan
828c09509b const: constify remaining file_operations
[akpm@linux-foundation.org: fix KVM]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:11 -07:00
Chris Mason
9c2693c924 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable into for-linus 2009-10-01 17:24:44 -04:00
Josef Bacik
fbf1908744 Btrfs: fix data space leak fix
There is a problem where page_mkwrite can be called on a dirtied page that
already has a delalloc range associated with it.  The fix is to clear any
delalloc bits for the range we are dirtying so the space accounting gets
handled properly.  This is the same thing we do in the normal write case, so we
are consistent across the board.  With this patch we no longer leak reserved
space.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-01 17:10:23 -04:00
Christoph Hellwig
8aa38c31b7 Btrfs: remove duplicates of filemap_ helpers
Use filemap_fdatawrite_range and filemap_fdatawait_range instead of
local copies of the functions.  For filemap_fdatawait_range that
also means replacing the awkward old wait_on_page_writeback_range
calling convention with the regular filemap byte offsets.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-01 12:58:30 -04:00
Chris Mason
25472b880c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable into for-linus 2009-10-01 12:58:13 -04:00
Chris Mason
ab93dbecfb Btrfs: take i_mutex before generic_write_checks
btrfs_file_write was incorrectly calling generic_write_checks without
taking i_mutex.  This lead to problems with racing around i_size when
doing O_APPEND writes.

The fix here is to move i_mutex higher.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-01 12:29:10 -04:00
Christoph Hellwig
35d62a942d Btrfs: fix arguments to btrfs_wait_on_page_writeback_range
wait_on_page_writeback_range/btrfs_wait_on_page_writeback_range takes
a pagecache offset, not a byte offset into the file.  Shift the arguments
around to wait for the correct range

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-10-01 10:27:01 -04:00
Sage Weil
dd7e0b7b02 Btrfs: fix deadlock with free space handling and user transactions
If an ioctl-initiated transaction is open, we can't force a commit during
the free space checks in order to free up pinned extents or else we
deadlock.  Just ENOSPC instead.

A more satisfying solution that reserves space for the entire user
transaction up front is forthcoming...

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-29 19:50:07 -04:00
Sage Weil
1ab86aedbc Btrfs: fix error cases for ioctl transactions
Fix leak of vfsmount write reference and open_ioctl_trans reference on
ENOMEM.  Clean up the error paths while we're at it.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-29 18:38:44 -04:00
Chris Ball
3baf0bed0a Btrfs: Use CONFIG_BTRFS_POSIX_ACL to enable ACL code
We've already defined CONFIG_BTRFS_POSIX_ACL in Kconfig, but we're
currently not using it and are testing CONFIG_FS_POSIX_ACL instead.
CONFIG_FS_POSIX_ACL states "Never use this symbol for ifdefs".

Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-29 13:51:05 -04:00
Julia Lawall
fd2696f399 Btrfs: introduce missing kfree
Error handling code following a kzalloc should free the allocated data.

The semantic match that finds the problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
statement S;
expression E;
identifier f,f1,l;
position p1,p2;
expression *ptr != NULL;
@@

x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
     when != if (...) { <+...x...+> }
(
x->f1 = E
|
 (x->f1 == NULL || ...)
|
 f(...,x->f1,...)
)
...>
(
 return \(0\|<+...x...+>\|ptr\);
|
 return@p2 ...;
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-29 13:51:04 -04:00
Chris Ball
49cf6f4529 Btrfs: Fix setting umask when POSIX ACLs are not enabled
We currently set sb->s_flags |= MS_POSIXACL unconditionally, which is
incorrect -- it tells the VFS that it shouldn't set umask because we
will, yet we don't set it ourselves if we aren't using POSIX ACLs, so
the umask ends up ignored.

Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-29 13:51:04 -04:00
Josef Bacik
9ed74f2dba Btrfs: proper -ENOSPC handling
At the start of a transaction we do a btrfs_reserve_metadata_space() and
specify how many items we plan on modifying.  Then once we've done our
modifications and such, just call btrfs_unreserve_metadata_space() for
the same number of items we reserved.

For keeping track of metadata needed for data I've had to add an extent_io op
for when we merge extents.  This lets us track space properly when we are doing
sequential writes, so we don't end up reserving way more metadata space than
what we need.

The only place where the metadata space accounting is not done is in the
relocation code.  This is because Yan is going to be reworking that code in the
near future, so running btrfs-vol -b could still possibly result in a ENOSPC
related panic.  This patch also turns off the metadata_ratio stuff in order to
allow users to more efficiently use their disk space.

This patch makes it so we track how much metadata we need for an inode's
delayed allocation extents by tracking how many extents are currently
waiting for allocation.  It introduces two new callbacks for the
extent_io tree's, merge_extent_hook and split_extent_hook.  These help
us keep track of when we merge delalloc extents together and split them
up.  Reservations are handled prior to any actually dirty'ing occurs,
and then we unreserve after we dirty.

btrfs_unreserve_metadata_for_delalloc() will make the appropriate
unreservations as needed based on the number of reservations we
currently have and the number of extents we currently have.  Doing the
reservation outside of doing any of the actual dirty'ing lets us do
things like filemap_flush() the inode to try and force delalloc to
happen, or as a last resort actually start allocation on all delalloc
inodes in the fs.  This has survived dbench, fs_mark and an fsx torture
test.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-28 16:29:42 -04:00
Alexey Dobriyan
f0f37e2f77 const: mark struct vm_struct_operations
* mark struct vm_area_struct::vm_ops as const
* mark vm_ops in AGP code

But leave TTM code alone, something is fishy there with global vm_ops
being used.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-27 11:39:25 -07:00
Linus Torvalds
dc2af6a6bc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (42 commits)
  Btrfs: hash the btree inode during  fill_super
  Btrfs: relocate file extents in clusters
  Btrfs: don't rename file into dummy directory
  Btrfs: check size of inode backref before adding hardlink
  Btrfs: fix releasepage to avoid unlocking extents we haven't locked
  Btrfs: Fix test_range_bit for whole file extents
  Btrfs: fix errors handling cached state in set/clear_extent_bit
  Btrfs: fix early enospc during balancing
  Btrfs: deal with NULL space info
  Btrfs: account for space used by the super mirrors
  Btrfs: fix extent entry threshold calculation
  Btrfs: remove dead code
  Btrfs: fix bitmap size tracking
  Btrfs: don't keep retrying a block group if we fail to allocate a cluster
  Btrfs: make balance code choose more wisely when relocating
  Btrfs: fix arithmetic error in clone ioctl
  Btrfs: add snapshot/subvolume destroy ioctl
  Btrfs: change how subvolumes are organized
  Btrfs: do not reuse objectid of deleted snapshot/subvol
  Btrfs: speed up snapshot dropping
  ...
2009-09-24 08:57:29 -07:00
Linus Torvalds
db16826367 Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
* 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6: (21 commits)
  HWPOISON: Enable error_remove_page on btrfs
  HWPOISON: Add simple debugfs interface to inject hwpoison on arbitary PFNs
  HWPOISON: Add madvise() based injector for hardware poisoned pages v4
  HWPOISON: Enable error_remove_page for NFS
  HWPOISON: Enable .remove_error_page for migration aware file systems
  HWPOISON: The high level memory error handler in the VM v7
  HWPOISON: Add PR_MCE_KILL prctl to control early kill behaviour per process
  HWPOISON: shmem: call set_page_dirty() with locked page
  HWPOISON: Define a new error_remove_page address space op for async truncation
  HWPOISON: Add invalidate_inode_page
  HWPOISON: Refactor truncate to allow direct truncating of page v2
  HWPOISON: check and isolate corrupted free pages v2
  HWPOISON: Handle hardware poisoned pages in try_to_unmap
  HWPOISON: Use bitmask/action code for try_to_unmap behaviour
  HWPOISON: x86: Add VM_FAULT_HWPOISON handling to x86 page fault handler v2
  HWPOISON: Add poison check to page fault handling
  HWPOISON: Add basic support for poisoned pages in fault handler v3
  HWPOISON: Add new SIGBUS error codes for hardware poison signals
  HWPOISON: Add support for poison swap entries v2
  HWPOISON: Export some rmap vma locking to outside world
  ...
2009-09-24 07:53:22 -07:00
Chris Mason
54bcf382da Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable into for-linus
Conflicts:
	fs/btrfs/super.c
2009-09-24 10:00:58 -04:00
Yan Zheng
c65ddb52dc Btrfs: hash the btree inode during fill_super
The snapshot deletion  patches dropped this line, but the inode
needs to be hashed.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-24 09:24:43 -04:00
Yan, Zheng
0257bb82d2 Btrfs: relocate file extents in clusters
The extent relocation code copy file extents one by one when
relocating data block group. This is inefficient if file
extents are small. This patch makes the relocation code copy
file extents in clusters. So we can can make better use of
read-ahead.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-24 09:17:31 -04:00
Yan, Zheng
f679a84034 Btrfs: don't rename file into dummy directory
A recent change enforces only one access point to each subvolume. The first
directory entry (the one added when the subvolume/snapshot was created) is
treated as valid access point, all other subvolume links are linked to dummy
empty directories. The dummy directories are temporary inodes that only in
memory, so we can not rename file into them.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-24 09:17:31 -04:00
Yan, Zheng
a571952143 Btrfs: check size of inode backref before adding hardlink
For every hardlink in btrfs, there is a corresponding inode back
reference. All inode back references for hardlinks in a given
directory are stored in single b-tree item. The size of b-tree item
is limited by the size of b-tree leaf, so we can only create limited
number of hardlinks to a given file in a directory.

The original code lacks of the check, it oops if the number of
hardlinks goes over the limit. This patch fixes the issue by adding
check to btrfs_link and btrfs_rename.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-24 09:17:31 -04:00
Chris Mason
11ef160fda Btrfs: fix releasepage to avoid unlocking extents we haven't locked
During releasepage, we try to drop any extent_state structs for the
bye offsets of the page we're releaseing.  But the code was incorrectly
telling clear_extent_bit to delete the state struct unconditionallly.

Normally this would be fine because we have the page locked, but other
parts of btrfs will lock down an entire extent, the most common place
being IO completion.

releasepage was deleting the extent state without first locking the extent,
which may result in removing a state struct that another process had
locked down.  The fix here is to leave the NODATASUM and EXTENT_LOCKED
bits alone in releasepage.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-23 20:30:53 -04:00
Chris Mason
46562cec98 Btrfs: Fix test_range_bit for whole file extents
If test_range_bit finds an extent that goes all the way to (u64)-1, it
can incorrectly wrap the u64 instead of treaing it like the end of
the address space.

This just adds a check for the highest possible offset so we don't wrap.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-23 20:30:52 -04:00
Chris Mason
42daec299b Btrfs: fix errors handling cached state in set/clear_extent_bit
Both set and clear_extent_bit allow passing a cached
state struct to reduce rbtree search times.  clear_extent_bit
was improperly bypassing some of the checks around making sure
the extent state fields were correct for a given operation.

The fix used here (from Yan Zheng) is to use the hit_next
goto target instead of jumping all the way down to start clearing
bits without making sure the cached state was exactly correct
for the operation we were doing.

This also fixes up the setting of the start variable for both
ops in the case where we find an overlapping extent that
begins before the range we want to change.  In both cases
we were incorrectly going backwards from the original
requested change.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-23 20:30:52 -04:00
Chris Mason
7ce618db98 Btrfs: fix early enospc during balancing
We now do extra checks before a balance to make sure
there is room for the balance to take place.  One of
the checks was testing to see if we were trying to
balance away the last block group of a given type.

If there is no space available for new chunks, we
should not try and balance away the last block group
of a give type.  But, the code wasn't checking for
available chunk space, and so it was exiting too soon.

The fix here is to combine some of the checks and make
sure we try to allocate new chunks when we're balancing
the last block group.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-22 14:48:44 -04:00
Chris Mason
33b4d47f5e Btrfs: deal with NULL space info
After a balance it is briefly possible for the space info
field in the inode to be NULL.  This adds some checks
to make sure things properly deal with the NULL value.


Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-22 14:45:50 -04:00
Linus Torvalds
342ff1a1b5 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits)
  trivial: fix typo in aic7xxx comment
  trivial: fix comment typo in drivers/ata/pata_hpt37x.c
  trivial: typo in kernel-parameters.txt
  trivial: fix typo in tracing documentation
  trivial: add __init/__exit macros in drivers/gpio/bt8xxgpio.c
  trivial: add __init macro/ fix of __exit macro location in ipmi_poweroff.c
  trivial: remove unnecessary semicolons
  trivial: Fix duplicated word "options" in comment
  trivial: kbuild: remove extraneous blank line after declaration of usage()
  trivial: improve help text for mm debug config options
  trivial: doc: hpfall: accept disk device to unload as argument
  trivial: doc: hpfall: reduce risk that hpfall can do harm
  trivial: SubmittingPatches: Fix reference to renumbered step
  trivial: fix typos "man[ae]g?ment" -> "management"
  trivial: media/video/cx88: add __init/__exit macros to cx88 drivers
  trivial: fix typo in CONFIG_DEBUG_FS in gcov doc
  trivial: fix missing printk space in amd_k7_smp_check
  trivial: fix typo s/ketymap/keymap/ in comment
  trivial: fix typo "to to" in multiple files
  trivial: fix typos in comments s/DGBU/DBGU/
  ...
2009-09-22 07:51:45 -07:00
Alexey Dobriyan
6e1d5dcc2b const: mark remaining inode_operations as const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Alexey Dobriyan
7f09410bbc const: mark remaining address_space_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Alexey Dobriyan
b87221de6a const: mark remaining super_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Josef Bacik
1b2da372b0 Btrfs: account for space used by the super mirrors
As we get closer to proper -ENOSPC handling in btrfs, we need more accurate
space accounting for the space info's.  Currently we exclude the free space for
the super mirrors, but the space they take up isn't accounted for in any of the
counters.  This patch introduces bytes_super, which keeps track of the amount
of bytes used for a super mirror in the block group cache and space info.  This
makes sure that our free space caclucations will be completely accurate.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 19:23:50 -04:00
Josef Bacik
25891f796d Btrfs: fix extent entry threshold calculation
There is a slight problem with the extent entry threshold calculation for the
free space cache.  We only adjust the threshold down as we add bitmaps, but
never actually adjust the threshold up as we add bitmaps.  This means we could
fragment the free space so badly that we end up using all bitmaps to describe
the free space, use all the free space which would result in the bitmaps being
freed, but then go to add free space again as we delete things and immediately
add bitmaps since the extent threshold would still be 0.  Now as we free
bitmaps the extent threshold will be ratcheted up to allow more extent entries
to be added.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 19:23:50 -04:00
Josef Bacik
f61408b81c Btrfs: remove dead code
This patch removes a bunch of dead code from the snapshot removal stuff.  It
was confusing me when doing the metadata ENOSPC stuff so I killed it.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 19:23:49 -04:00
Josef Bacik
f019f4264a Btrfs: fix bitmap size tracking
When we first go to add free space, we allocate a new info and set the offset
and bytes to the space we are adding.  This is fine, except we actually set the
size of a bitmap as we set the bits in it, so if we add space to a bitmap, we'd
end up counting the same space twice.  This isn't a huge deal, it just makes
the allocator behave weirdly since it will think that a bitmap entry has more
space than it ends up actually having.  I used a BUG_ON() to catch when this
problem happened, and with this patch I no longer get the BUG_ON().

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 19:23:49 -04:00
Josef Bacik
0a24325e6d Btrfs: don't keep retrying a block group if we fail to allocate a cluster
The box can get locked up in the allocator if we happen upon a block group
under these conditions:

1) During a commit, so caching threads cannot make progress
2) Our block group currently is in the middle of being cached
3) Our block group currently has plenty of free space in it
4) Our block group is so fragmented that it ends up having no free space chunks
larger than min_bytes calculated by btrfs_find_space_cluster.

What happens is we try and do btrfs_find_space_cluster, which fails because it
is unable to find enough free space chunks that are large than min_bytes and
are close enough together.  Since the block group is not cached we do a
wait_block_group_cache_progress, which waits for the number of bytes we need,
except the block group already has _plenty_ of free space, its just severely
fragmented, so we loop and try again, ad infinitum.  This patch keeps us from
waiting on the block group to finish caching if we failed to find a free space
cluster before.  It also makes sure that we don't even try to find a free space
cluster if we are on our last loop in the allocator, since we will have tried
everything at this point at it is futile.

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 19:23:49 -04:00
Josef Bacik
ba1bf4818b Btrfs: make balance code choose more wisely when relocating
Currently, we can panic the box if the first block group we go to move is of a
type where there is no space left to move those extents.  For example, if we
fill the disk up with data, and then we try to balance and we have no room to
move the data nor room to allocate new chunks, we will panic.  Change this by
checking to see if we have room to move this chunk around, and if not, return
-ENOSPC and move on to the next chunk.  This will make sure we remove block
groups that are moveable, like if we have alot of empty metadata block groups,
and then that way we make room to be able to balance our data chunks as well.
Tested this with an fs that would panic on btrfs-vol -b normally, but no longer
panics with this patch.

V1->V2:
-actually search for a free extent on the device to make sure we can allocate a
chunk if need be.

-fix btrfs_shrink_device to make sure we actually try to relocate all the
chunks, and then if we can't return -ENOSPC so if we are doing a btrfs-vol -r
we don't remove the device with data still on it.

-check to make sure the block group we are going to relocate isn't the last one
in that particular space

-fix a bug in btrfs_shrink_device where we would change the device's size and
not fix it if we fail to do our relocate

Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 19:23:48 -04:00
Sage Weil
1fb58a6051 Btrfs: fix arithmetic error in clone ioctl
Fix an arithmetic error that was breaking extents cloned via the clone
ioctl starting in the second half of a file.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 16:00:27 -04:00
Yan, Zheng
76dda93c6a Btrfs: add snapshot/subvolume destroy ioctl
This patch adds snapshot/subvolume destroy ioctl.  A subvolume that isn't being
used and doesn't contains links to other subvolumes can be destroyed.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 16:00:26 -04:00
Yan, Zheng
4df27c4d5c Btrfs: change how subvolumes are organized
btrfs allows subvolumes and snapshots anywhere in the directory tree.
If we snapshot a subvolume that contains a link to other subvolume
called subvolA, subvolA can be accessed through both the original
subvolume and the snapshot. This is similar to creating hard link to
directory, and has the very similar problems.

The aim of this patch is enforcing there is only one access point to
each subvolume. Only the first directory entry (the one added when
the subvolume/snapshot was created) is treated as valid access point.
The first directory entry is distinguished by checking root forward
reference. If the corresponding root forward reference is missing,
we know the entry is not the first one.

This patch also adds snapshot/subvolume rename support, the code
allows rename subvolume link across subvolumes.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 15:56:00 -04:00
Yan, Zheng
13a8a7c8c4 Btrfs: do not reuse objectid of deleted snapshot/subvol
The new back reference format does not allow reusing objectid of
deleted snapshot/subvol. So we use ++highest_objectid to allocate
objectid for new snapshot/subvol.

Now we use ++highest_objectid to allocate objectid for both new inode
and new snapshot/subvolume, so this patch removes 'find hole' code in
btrfs_find_free_objectid.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 15:56:00 -04:00
Yan, Zheng
1c4850e21d Btrfs: speed up snapshot dropping
This patch contains two changes to avoid unnecessary tree block reads during
snapshot dropping.

First, check tree block's reference count and flags before reading the tree
block. if reference count > 1 and there is no need to update backrefs, we can
avoid reading the tree block.

Second, save when snapshot was created in root_key.offset. we can compare block
pointer's generation with snapshot's creation generation during updating
backrefs. If a given block was created before snapshot was created, the
snapshot can't be the tree block's owner. So we can avoid reading the block.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-21 15:55:59 -04:00
Joe Perches
a419aef8b8 trivial: remove unnecessary semicolons
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-21 15:14:58 +02:00
Chris Mason
b917b7c3be Btrfs: search for an allocation hint while filling file COW
The allocator has some nice knobs for sending hints about where
to try and allocate new blocks, but when we're doing file allocations
we're not sending any hint at all.

This commit adds a simple extent map search to see if we can
quickly and easily find a hint for the allocator.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-18 16:08:52 -04:00
Chris Mason
f85d7d6c8f Btrfs: properly honor wbc->nr_to_write changes
When btrfs fills a delayed allocation, it tries to increase
the wbc nr_to_write to cover a big part of allocation.  The
theory is that we're doing contiguous IO and writing a few
more blocks will save seeks overall at a very low cost.

The problem is that extent_write_cache_pages could ignore
the new higher nr_to_write if nr_to_write had already gone
down to zero.  We fix that by rechecking the nr_to_write
for every page that is processed in the pagevec.

This updates the math around bumping the nr_to_write value
to make sure we don't leave a tiny amount of IO hanging
around for the very end of a new extent.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-09-18 16:08:46 -04:00